NO763422L - - Google Patents
Info
- Publication number
- NO763422L NO763422L NO763422A NO763422A NO763422L NO 763422 L NO763422 L NO 763422L NO 763422 A NO763422 A NO 763422A NO 763422 A NO763422 A NO 763422A NO 763422 L NO763422 L NO 763422L
- Authority
- NO
- Norway
- Prior art keywords
- sludge
- hydrogen peroxide
- metal ion
- treatment
- lime
- Prior art date
Links
- 239000010802 sludge Substances 0.000 claims description 50
- MHAJPDPJQMAIIY-UHFFFAOYSA-N Hydrogen peroxide Chemical compound OO MHAJPDPJQMAIIY-UHFFFAOYSA-N 0.000 claims description 38
- 238000000034 method Methods 0.000 claims description 34
- 239000007787 solid Substances 0.000 claims description 17
- 238000000926 separation method Methods 0.000 claims description 16
- 239000007788 liquid Substances 0.000 claims description 14
- 229910021645 metal ion Inorganic materials 0.000 claims description 12
- 238000004062 sedimentation Methods 0.000 claims description 8
- 239000002253 acid Substances 0.000 claims description 5
- 239000003513 alkali Substances 0.000 claims description 3
- 239000010815 organic waste Substances 0.000 claims description 3
- 238000005119 centrifugation Methods 0.000 claims description 2
- 229910052742 iron Inorganic materials 0.000 claims description 2
- 239000010801 sewage sludge Substances 0.000 claims description 2
- RBTARNINKXHZNM-UHFFFAOYSA-K iron trichloride Chemical compound Cl[Fe](Cl)Cl RBTARNINKXHZNM-UHFFFAOYSA-K 0.000 description 24
- 238000011282 treatment Methods 0.000 description 24
- 235000008733 Citrus aurantifolia Nutrition 0.000 description 18
- 235000011941 Tilia x europaea Nutrition 0.000 description 18
- 239000004571 lime Substances 0.000 description 18
- 229910021578 Iron(III) chloride Inorganic materials 0.000 description 13
- 238000001914 filtration Methods 0.000 description 10
- 239000000126 substance Substances 0.000 description 9
- 239000002699 waste material Substances 0.000 description 8
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 6
- 239000003153 chemical reaction reagent Substances 0.000 description 6
- 239000012065 filter cake Substances 0.000 description 6
- 239000000706 filtrate Substances 0.000 description 6
- 239000011651 chromium Substances 0.000 description 5
- 230000006835 compression Effects 0.000 description 5
- 238000007906 compression Methods 0.000 description 5
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 5
- RWSOTUBLDIXVET-UHFFFAOYSA-N Dihydrogen sulfide Chemical compound S RWSOTUBLDIXVET-UHFFFAOYSA-N 0.000 description 4
- 229910052804 chromium Inorganic materials 0.000 description 4
- 239000004744 fabric Substances 0.000 description 4
- BAUYGSIQEAFULO-UHFFFAOYSA-L iron(2+) sulfate (anhydrous) Chemical compound [Fe+2].[O-]S([O-])(=O)=O BAUYGSIQEAFULO-UHFFFAOYSA-L 0.000 description 4
- 239000011368 organic material Substances 0.000 description 4
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 3
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 3
- 238000013019 agitation Methods 0.000 description 3
- 229910001873 dinitrogen Inorganic materials 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 239000008394 flocculating agent Substances 0.000 description 3
- 239000010842 industrial wastewater Substances 0.000 description 3
- 238000006386 neutralization reaction Methods 0.000 description 3
- 239000000843 powder Substances 0.000 description 3
- 239000002351 wastewater Substances 0.000 description 3
- VTYYLEPIZMXCLO-UHFFFAOYSA-L Calcium carbonate Chemical compound [Ca+2].[O-]C([O-])=O VTYYLEPIZMXCLO-UHFFFAOYSA-L 0.000 description 2
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 description 2
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 2
- NBIIXXVUZAFLBC-UHFFFAOYSA-N Phosphoric acid Chemical compound OP(O)(O)=O NBIIXXVUZAFLBC-UHFFFAOYSA-N 0.000 description 2
- CDBYLPFSWZWCQE-UHFFFAOYSA-L Sodium Carbonate Chemical compound [Na+].[Na+].[O-]C([O-])=O CDBYLPFSWZWCQE-UHFFFAOYSA-L 0.000 description 2
- VSCWAEJMTAWNJL-UHFFFAOYSA-K aluminium trichloride Chemical compound Cl[Al](Cl)Cl VSCWAEJMTAWNJL-UHFFFAOYSA-K 0.000 description 2
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 2
- 238000002485 combustion reaction Methods 0.000 description 2
- 150000001875 compounds Chemical class 0.000 description 2
- 239000000428 dust Substances 0.000 description 2
- 230000007613 environmental effect Effects 0.000 description 2
- 239000000295 fuel oil Substances 0.000 description 2
- 229910052602 gypsum Inorganic materials 0.000 description 2
- 239000010440 gypsum Substances 0.000 description 2
- 230000006872 improvement Effects 0.000 description 2
- XEEYBQQBJWHFJM-UHFFFAOYSA-N iron Substances [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- -1 iron ions Chemical class 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- 239000001301 oxygen Substances 0.000 description 2
- 229910052760 oxygen Inorganic materials 0.000 description 2
- 238000011085 pressure filtration Methods 0.000 description 2
- 239000000047 product Substances 0.000 description 2
- 150000003839 salts Chemical class 0.000 description 2
- 239000010865 sewage Substances 0.000 description 2
- 231100000331 toxic Toxicity 0.000 description 2
- 230000002588 toxic effect Effects 0.000 description 2
- 229910052720 vanadium Inorganic materials 0.000 description 2
- 239000004343 Calcium peroxide Substances 0.000 description 1
- 150000007513 acids Chemical class 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 238000005273 aeration Methods 0.000 description 1
- 230000004931 aggregating effect Effects 0.000 description 1
- 229910000147 aluminium phosphate Inorganic materials 0.000 description 1
- DIZPMCHEQGEION-UHFFFAOYSA-H aluminium sulfate (anhydrous) Chemical compound [Al+3].[Al+3].[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O DIZPMCHEQGEION-UHFFFAOYSA-H 0.000 description 1
- 229910000019 calcium carbonate Inorganic materials 0.000 description 1
- LHJQIRIGXXHNLA-UHFFFAOYSA-N calcium peroxide Chemical compound [Ca+2].[O-][O-] LHJQIRIGXXHNLA-UHFFFAOYSA-N 0.000 description 1
- 235000019402 calcium peroxide Nutrition 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 238000011109 contamination Methods 0.000 description 1
- 239000002781 deodorant agent Substances 0.000 description 1
- BUACSMWVFUNQET-UHFFFAOYSA-H dialuminum;trisulfate;hydrate Chemical compound O.[Al+3].[Al+3].[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O BUACSMWVFUNQET-UHFFFAOYSA-H 0.000 description 1
- 230000029087 digestion Effects 0.000 description 1
- VTIIJXUACCWYHX-UHFFFAOYSA-L disodium;carboxylatooxy carbonate Chemical compound [Na+].[Na+].[O-]C(=O)OOC([O-])=O VTIIJXUACCWYHX-UHFFFAOYSA-L 0.000 description 1
- 229910052500 inorganic mineral Inorganic materials 0.000 description 1
- RUTXIHLAWFEWGM-UHFFFAOYSA-H iron(3+) sulfate Chemical compound [Fe+3].[Fe+3].[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O RUTXIHLAWFEWGM-UHFFFAOYSA-H 0.000 description 1
- 229910000359 iron(II) sulfate Inorganic materials 0.000 description 1
- 229910000360 iron(III) sulfate Inorganic materials 0.000 description 1
- 239000007791 liquid phase Substances 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 239000011707 mineral Substances 0.000 description 1
- 150000007522 mineralic acids Chemical class 0.000 description 1
- 230000007935 neutral effect Effects 0.000 description 1
- 230000009965 odorless effect Effects 0.000 description 1
- 150000007524 organic acids Chemical class 0.000 description 1
- 235000005985 organic acids Nutrition 0.000 description 1
- 150000001451 organic peroxides Chemical class 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- JRKICGRDRMAZLK-UHFFFAOYSA-L persulfate group Chemical group S(=O)(=O)([O-])OOS(=O)(=O)[O-] JRKICGRDRMAZLK-UHFFFAOYSA-L 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 230000029219 regulation of pH Effects 0.000 description 1
- 238000009418 renovation Methods 0.000 description 1
- 239000005871 repellent Substances 0.000 description 1
- 230000002940 repellent Effects 0.000 description 1
- 230000000717 retained effect Effects 0.000 description 1
- 239000002002 slurry Substances 0.000 description 1
- 229910000029 sodium carbonate Inorganic materials 0.000 description 1
- 229960001922 sodium perborate Drugs 0.000 description 1
- 229940045872 sodium percarbonate Drugs 0.000 description 1
- YKLJGMBLPUQQOI-UHFFFAOYSA-M sodium;oxidooxy(oxo)borane Chemical compound [Na+].[O-]OB=O YKLJGMBLPUQQOI-UHFFFAOYSA-M 0.000 description 1
- 238000001179 sorption measurement Methods 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/52—Treatment of water, waste water, or sewage by flocculation or precipitation of suspended impurities
- C02F1/5236—Treatment of water, waste water, or sewage by flocculation or precipitation of suspended impurities using inorganic agents
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/72—Treatment of water, waste water, or sewage by oxidation
- C02F1/722—Oxidation by peroxides
Landscapes
- Chemical & Material Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Hydrology & Water Resources (AREA)
- Engineering & Computer Science (AREA)
- Environmental & Geological Engineering (AREA)
- Water Supply & Treatment (AREA)
- Organic Chemistry (AREA)
- Inorganic Chemistry (AREA)
- Treatment Of Sludge (AREA)
- Separation Of Suspended Particles By Flocculating Agents (AREA)
Description
Denne oppfinnelse angÄr faststoff-vÊske-separasjon av organiske materialer ved behandling av kloakkavfall, industrielt avfallsvann og lignende. Mer spesielt angÄr oppfinnelsen en fremgangsmÄte for ovennevnte formÄl hvor det til slammet til- This invention relates to solid-liquid separation of organic materials in the treatment of sewage waste, industrial waste water and the like. More particularly, the invention relates to a method for the above-mentioned purpose, where the sludge
settes hydrogenperoksyd (I-^C^) og et metall-ion med minst 3 positive ladninger, og hvor pH-verdien holdes ved eller under 9, slik at de suspenderte organiske materialer omdannes til lett separable eller filtrerbare partikler. hydrogen peroxide (I-^C^) and a metal ion with at least 3 positive charges are added, and where the pH value is kept at or below 9, so that the suspended organic materials are converted into easily separable or filterable particles.
Kjemisk, biologisk eller annen behandling er i det siste blitt anvendt for behandling av kloakkavfall og industrielt avfallsvann. De biologiske behandlinger som gir avgangsstrÞmmer med lavere biologisk oksygenbehov (BOD) eller kjemisk oksygenbehov (COD) etter behandlingen er i den senere tid blitt mer ak-septert nÄr det gjelder kontroll av avfallsvann. I tilfeller hvor kjemisk eller fysikalsk behandling foretas, har man gÄtt over til biologisk behandling eller kombinasjoner hvor denne inn-gÄr. Ved alle de ovenfor nevnte behandlingsmÄter er det nÞdvendig Ä fjerne organiske materialer som er uopplÞselige eller suspen-dert i vann. For oppnÄelse av en hurtig separasjon av disse anvendes slike reagenser som kalk, jern(III)klorid, jern(II)sulfat og makromolekylÊre fnokkingsmidler. Chemical, biological or other treatment has recently been used for the treatment of sewage waste and industrial waste water. The biological treatments that provide waste streams with a lower biological oxygen demand (BOD) or chemical oxygen demand (COD) after the treatment have recently become more accepted when it comes to controlling waste water. In cases where chemical or physical treatment is carried out, it has been switched to biological treatment or combinations where this is included. In all of the above-mentioned treatment methods, it is necessary to remove organic materials that are insoluble or suspended in water. To achieve a rapid separation of these, such reagents as lime, iron (III) chloride, iron (II) sulphate and macromolecular flocculating agents are used.
En typisk slambehandlingsmetode som finner utstrakt anvendelse, gĂ„r hovedsakelig ut pĂ„ anvendelse av et fĂžrste sedimenteringsbasseng, en luftetank, et siste sedimenteringsbasseng og en oppslutningstank for det avgĂ„ende slam. Fraskillelse av de organiske faste stoffer er nĂždvendig i disse trinn for behandling av rĂ„slam fra det fĂžrste sedimenteringsbasseng, avgĂ„ende slam fra det siste sedimenteringsbasseng og oppsluttet slam fra oppslut-ningstanken. Faststoff-vĂŠske-separasjon nĂ„r det gjelder disse slammaterialer,er hittil blitt utfĂžrt med kalk og jern(III)klorid, og i den senere tid i noen tilfeller med makromolekylĂŠre fnokkingsmidler. Disse reagenser er imidlertid ikke generelt tilfredsstillende for faststoff-vĂŠske-separasjonen av hvilket som helst slam.. â A typical sludge treatment method that finds widespread use mainly involves the use of a first sedimentation basin, an aeration tank, a final sedimentation basin and a digestion tank for the outgoing sludge. Separation of the organic solids is necessary in these stages for the treatment of raw sludge from the first sedimentation basin, outgoing sludge from the last sedimentation basin and suspended sludge from the settling tank. Solid-liquid separation in the case of these sludge materials has so far been carried out with lime and iron(III) chloride, and more recently in some cases with macromolecular flocculants. However, these reagents are not generally satisfactory for the solid-liquid separation of any sludge.. â
I eksempelvis et kloakkslamanlegg .som mottar industrielt avfallsvann blir en slamkake egnet for faststoff-vÊske-separasjon fÞrst dannet ved tilsetning av et overskudd av kalk og jern(III)-klorid; for det avgÄende slam er disse reagenser ikke tilfredsstillende for best mulig dannelse av fnokker. Reagenset blir faktisk inkorporert porsjonsvis i rÄslammet ved behandlingen. FÞlgelig blir mengden av kalk og jern(III)klorid som anvendes In, for example, a sewage sludge plant that receives industrial waste water, a sludge cake suitable for solid-liquid separation is first formed by adding an excess of lime and iron(III) chloride; for the outgoing sludge, these reagents are not satisfactory for the best possible formation of flocs. The reagent is actually incorporated in portions into the raw sludge during treatment. Consequently, the amount of lime and iron(III) chloride used is
Þket, med det resultat at ogsÄ mengden av dannet kake Þkes, slik at transport og forbrenning av kaken sÄvel som behandlingen av asken etter forbrenningen blir meget kostbar. Videre er filtratet etter faststoff-vÊske-separasjonen alkalisk p.g.a. kalken, og nÞytralisering av filtratet med svovelsyre resulterer i dannelse av gips, som tilstopper ledninger; man kan heller ikke se bort fra utgiftene til reperasjon og vedlikehold av ledninger. Videre er kalk uÞnsket sett fra et miljÞmessig og hygienisk synspunkt, increased, with the result that the amount of cake formed is also increased, so that the transport and burning of the cake as well as the treatment of the ash after burning becomes very expensive. Furthermore, the filtrate after the solid-liquid separation is alkaline due to the lime, and neutralization of the filtrate with sulfuric acid results in the formation of gypsum, which clogs pipes; nor can you ignore the costs of repairing and maintaining cables. Furthermore, lime is undesirable from an environmental and hygienic point of view,
idet den - siden den foreligger i pulverform - bidrar til stĂžv-forurensning og i noen tilfeller inneholder meget krom avhengig av opprinnelsen. PĂ„ den annen side er mange makromolekylĂŠre fnokkingsmidler giftige p.g.a. sin molekylstruktur, slik at lĂžs-ningen etter faststoff-vĂŠske-separasjonen muligens vil vĂŠre skadelig for organismene hvis den returneres til det aktive slam. as it - since it is in powder form - contributes to dust pollution and in some cases contains a lot of chromium depending on the origin. On the other hand, many macromolecular repellents are toxic due to its molecular structure, so that the solution after the solid-liquid separation will possibly be harmful to the organisms if it is returned to the activated sludge.
I henhold til en fremgangsmÄte til behandling av renovasjonsavfall anvendes hydrogenperoksyd for faststoff-vÊske-sepa-ras jonen, enten alene eller i kombinasjon med jern(II)sulfat, According to a method for the treatment of waste disposal, hydrogen peroxide is used for the solid-liquid separation, either alone or in combination with iron (II) sulphate,
eller sistnevnte anvendes sammen med kalk. Hydrogenperoksyd kan godt anvendes alene for faststoff-vÊske-separasjon av det organiske slam, men de fnokker som dannes er myke og smuldrer' lett, og den pÄfÞlgende filtrering og avvanning kan vÊre vanskelig og avhenger av slike betingelser som agitering, pH og temperatur. Ved anvendelse av hydrogenperoksyd og jern(II)sulfat strÞmmer de tover-dige jern-ioner til filtratet fra faststoff-vÊske-separasjonen og kan skade organismene ved tilbakefÞring til det trinn hvor det aktive slam behandles, selv om det dannes fnokker som knapt pÄ-virkes av slike betingelser som agitering, pH og temperatur slik at filterkaken er tilfredsstillende. or the latter is used together with lime. Hydrogen peroxide can be used alone for solid-liquid separation of the organic sludge, but the flocs that are formed are soft and crumble easily, and the subsequent filtration and dewatering can be difficult and depends on such conditions as agitation, pH and temperature. When hydrogen peroxide and iron (II) sulfate are used, the bivalent iron ions flow to the filtrate from the solid-liquid separation and can damage the organisms when returned to the step where the activated sludge is treated, even if flecks are formed that hardly is affected by such conditions as agitation, pH and temperature so that the filter cake is satisfactory.
I henhold til den foreliggende oppfinnelse tilveiebringes en fremgangsmÄte til faststoff-vÊske-separasjon ved behandling av organisk avfallssiam,karakterisert vedat man tilsetter til slammet 0,5-30 vekt-% hydrogenperoksyd og 0,1-10 vekt-% av et metall-ion med minst 3 positive ladninger, pÄ basis av faststoffinnholdet i slammet, idet pH-verdien holdes ved eller under 9 ved tilsetning av en syre eller alkali for dannelse av stabile According to the present invention, a method is provided for solid-liquid separation when treating organic waste Siam, characterized by adding to the sludge 0.5-30% by weight of hydrogen peroxide and 0.1-10% by weight of a metal ion with at least 3 positive charges, based on the solids content of the sludge, the pH being maintained at or below 9 by the addition of an acid or alkali to form stable
organiske.fnokker, hvoretter faststoff-vĂŠske-separasjonen utfĂžres ved sedimentering, avsugning eller sentrifugering. organic flakes, after which the solid-liquid separation is carried out by sedimentation, suction or centrifugation.
Ved oppfinnelsen elimineres de ovenfor nevnte ulemper og tilveiebringer en behandlingsmÄte som medfÞrer mange fordeler sammenlignet med de kjente fremgangsmÄter ved behandling med kalk og jern(III)klorid, jern(II)sulfat, makromolekylÊre fnokkingsmidler og lignende. Den nÞyaktige virkemÄte eller mekanisme ved behandlingen med hydrogenperoksyd og et metall-ion med en valens pÄ minst 3 er ikke klarlagt, men det antas at metall-ionene ad-sorberes elektrisk pÄ aggregatene som dannes av organiske ulÞse-lige eller suspenderte materialer med hydrogenperoksyd ved aggre-gerende virkning, slik at den kombinerte bruk av de to stoffer ut-Þver en virkning som er ganske uventet ut fra bruken av hvert enkelt av stoffene. De fnokker som dannes er faktisk sÄ stabile at de ikke nedbrytes pÄ noen mÄte under pH-variasjoner, tempera-turforandringer og agitering og er filtrerbare. The invention eliminates the above-mentioned disadvantages and provides a method of treatment which entails many advantages compared to the known methods of treatment with lime and iron (III) chloride, iron (II) sulphate, macromolecular flocculating agents and the like. The exact mode of action or mechanism of the treatment with hydrogen peroxide and a metal ion with a valence of at least 3 has not been clarified, but it is assumed that the metal ions are adsorbed electrically on the aggregates formed by organic insoluble or suspended materials with hydrogen peroxide by aggregating effect, so that the combined use of the two substances exerts an effect which is quite unexpected from the use of each individual substance. The flocs that are formed are actually so stable that they do not break down in any way during pH variations, temperature changes and agitation and are filterable.
FremgangsmÄten i fÞlge oppfinnelsen skal nedenfor beskrives ved en utfÞrelsesform. For rÄslammet fra sand-sedimen-terings.bassenget ved kjemisk eller fysikalsk behandling, sedimen-teringsbassenget ved behandling av aktivt slam eller den fÞrste lagertank ved behandling av renovasjonsavfall, avgangsslammet fra béhandlingstrinnet for aktivt slam eller det oppsluttede slam fra det anaerobe behandlingstrinn anvendes 0,5-30 vekt-% hydrogenperoksyd uttrykt som rent stoff pÄ basis av faststoffinnholdet i slammet. Mer spesielt er omrÄdet 0,5-10 vekt-% for rÄslammet, 4-20 vekt-% for avgangsslammet og 0,5-30 vekt-% for det oppsluttede slam, hvor det siste Þkte omrÄde tilskrives samtidig fjer- . ning av slike produkter som hydrogensulfid og merkaptaner. Det er Þkonomisk fordelaktig Ä bestemme mengden i hvert tilfelle, i avhengighet av de i avfallsvannet foreliggende organiske materi-alers natur, reduserbare stoffer som dannes, med det oppsluttede slam etter den anaerobe behandling og lignende.. Hydrogenperoksyd betyr i det foreliggende ikke bare hydrogenperoksyd som sÄdant. men ogsÄ forbindelser som er opplÞselige i vann og utvikler hydrogenperoksyd, innbefattende natriumperborat, natriumpérkarbonat, kalsiumperoksyd, persulfater og organiske peroksyder. The method according to the invention will be described below by means of an embodiment. For the raw sludge from the sand-sedimentation basin for chemical or physical treatment, the sedimentation basin for treatment of activated sludge or the first storage tank for treatment of renovation waste, the waste sludge from the treatment step for activated sludge or the suspended sludge from the anaerobic treatment step, 0 is used, 5-30% by weight of hydrogen peroxide expressed as pure substance on the basis of the solids content of the sludge. More specifically, the range is 0.5-10% by weight for the raw sludge, 4-20% by weight for the waste sludge and 0.5-30% by weight for the suspended sludge, where the last increased area is attributed to simultaneous removal. ning of such products as hydrogen sulphide and mercaptans. It is economically advantageous to determine the quantity in each case, depending on the nature of the organic materials present in the waste water, reducible substances that are formed, with the trapped sludge after the anaerobic treatment and the like. Hydrogen peroxide in this context does not only mean hydrogen peroxide which such. but also compounds which are soluble in water and develop hydrogen peroxide, including sodium perborate, sodium percarbonate, calcium peroxide, persulphates and organic peroxides.
Metall-ionet med minst 3 positive ladninger tilsettesThe metal ion with at least 3 positive charges is added
i en mengde innen omrÄdet 0,1-10 vekt-% pÄ basis av faststoffinnholdet i slammet, spesielt 0,1-5% for rÄslam, 1-7% for avgangsslam og 0,1-10% for oppsluttet slam. Det er Þkonomisk mest fordelaktig Ä bestemme mengden i hvert tilfelle i avhengighet av det produkt som skal behandles. Som metall-ion med minst 3 in an amount within the range 0.1-10% by weight based on the solids content of the sludge, in particular 0.1-5% for raw sludge, 1-7% for waste sludge and 0.1-10% for suspended sludge. It is economically most advantageous to determine the quantity in each case depending on the product to be treated. As a metal ion with at least 3
<3+>3+ 3+ 6+ â.4+ 3+ â4+ valensladnmger nevnes Fe , Al , Cr , Cr , Ti , V , V , V og lignende. Cr som er giftig, og Ti- og V-forbindelser, som er kostbare, er derfor ikke godt egnet. I alminnelighet an-vender man fortrinnsvis Fe"^+ og Al^+. <3+>3+ 3+ 6+ â.4+ 3+ â4+ valence charge numbers are mentioned Fe , Al , Cr , Cr , Ti , V , V , V and the like. Cr, which is toxic, and Ti and V compounds, which are expensive, are therefore not well suited. In general, one preferably uses Fe"^+ and Al^+.
Valget av syre eller alkali til bruk ved pH-reguleringen til en verdi ved eller under 9 avhenger av slamvÊskeris egenskaper. Fortrinnsvis anvendes mineralsyrer, sÄ som saltsyre, svovelsyre og fosforsyre, og organiske syrer og salter med uorganiske syrer, sÄ som natriumhydroksyd, natriumkarbonat og kalsiumkarbonat. The choice of acid or alkali for use in the pH regulation to a value at or below 9 depends on the properties of the slurry. Mineral acids, such as hydrochloric acid, sulfuric acid and phosphoric acid, and organic acids and salts with inorganic acids, such as sodium hydroxide, sodium carbonate and calcium carbonate, are preferably used.
Da det aktive slam vanligvis foreligger i nĂŠr nĂžytral tilstandAs the activated sludge is usually present in an almost neutral state
i flytende fase, vil bruk av et konvensjonelt metallsalt, som f.eks. jern(III)klorid, aluminiumklorid, jern(III)sulfat eller aluminiumsulfat tillate en syre Ä bibeholdes etter adsorpsjon av metall-ionet pÄ fnokkene, med det resultat at pH-verdien vil opprettholdes ved eller under 9. pH ved eller under 4 er uÞnsket p.g.a. den korroderende virkning pÄ utstyret. in liquid phase, use of a conventional metal salt, such as e.g. ferric chloride, aluminum chloride, ferric sulfate or aluminum sulfate allow an acid to be retained after adsorption of the metal ion on the flakes, with the result that the pH will be maintained at or below 9. pH at or below 4 is undesirable because of. the corrosive effect on the equipment.
Fordeler ved den foreliggende oppfinnelse sammenlignet med fremgangsmÄten hvor det anvendes kalk og jern(III)klorid, Advantages of the present invention compared to the method where lime and iron (III) chloride are used,
er angitt nedenfor:is set out below:
(i) Bedre faststoff-vÊske-separasjon og bemerkelses-verdig forbedring i avvanningsgraden etter passasje gjennom filterdukén. Mens filtreringshastigheten er 4 kg/m 2.time ved den kjente metode for rÄslambehandling, oppnÄs 6 kg/m 2.time i henhold til oppfinnelsen. (ii) Behandlingen kan utfÞres med hÞyere faststoffinnhold i slammet. Mens faststoffinnholdet mÄ vÊre 2% eller lavere ved bruk av store filterpresser i henhold til den kjente metode, er det mulig Ä Þke det til 5% ved fremgangsmÄten i fÞlge oppfinnelsen. (iii) Markert nedsettelse i vanninnholdet i filterkaken. Mens dette er 50-55% ved den tidligere kjente metode, er det 40-50% ved fremgangsmÄten i fÞlge oppfinnelsen. ⹠(iv) . Nedsatt mengde fil terkake proporsjonalt med mengden av kalk, idet den er fra 1/2 til 3/4 av mengden i fÞlge den tidligere kjente metode avhengig av den mengde kalk som tilsettes. (v) Fordeler ved' forbrenningen av filterkaken. Mens temperaturen i ovnen var 600-700°C i fÞlge den tidligere kjente metode selv ved forbrenning med tungolje, ble temperaturen Þket til 800-900°C samtidig som mengden av tungolje ble redusert ved . fremgangsmÄten i fÞlge oppfinnelsen. Mengden av aske etter forbrenningen ble ogsÄ redusert til mindre enn 1/2 sammenlignet med den tidligere kjente metode. (vi) HÞy deodorantaktivitet.med derav fÞlgende miljÞ-messig forbedring. Hydrogenperoksyd omsettes med hydrogensulfid og merkaptaner, slik at arbeidsrommet blir nesten luktfritt. (vii) Filtratet behÞver ikke nÞytraliseres. Det er nÞdvendig Ä utfÞre nÞytraliseringen med svovelsyre ved den tidligere kjente metode, hvor filtratet har en pH pÄ 10-11. Ved fremgangsmÄten i fÞlge oppfinnelsen er pH-verdien innen omrÄdet 5-8, hvorved det blir unÞdvendig Ä nÞytralisere, med det resultat at tilstopping av ledningene med gips som dannes etter nÞy-traliseringen, ikke finner sted. (i) Better solid-liquid separation and remarkable improvement in the degree of dewatering after passage through the filter cloth. While the filtration rate is 4 kg/m 2 hour with the known method for raw sludge treatment, 6 kg/m 2 hour is achieved according to the invention. (ii) The treatment can be carried out with a higher solids content in the sludge. While the solids content must be 2% or lower when using large filter presses according to the known method, it is possible to increase it to 5% with the method according to the invention. (iii) Marked reduction in the water content of the filter cake. While this is 50-55% with the previously known method, it is 40-50% with the method according to the invention. ⹠(iv) . Reduced amount of fil ter cake proportional to the amount of lime, as it is from 1/2 to 3/4 of the amount according to the previously known method, depending on the amount of lime that is added. (v) Advantages of' the combustion of the filter cake. While the temperature in the furnace was 600-700°C according to the previously known method even when burning with heavy oil, the temperature was increased to 800-900°C at the same time as the amount of heavy oil was reduced by . the method according to the invention. The amount of ash after combustion was also reduced to less than 1/2 compared to the previously known method. (vi) High deodorant activity, with consequent environmental improvement. Hydrogen peroxide reacts with hydrogen sulphide and mercaptans, so that the work space becomes almost odorless. (vii) The filtrate does not need to be neutralized. It is necessary to carry out the neutralization with sulfuric acid by the previously known method, where the filtrate has a pH of 10-11. In the method according to the invention, the pH value is within the range 5-8, whereby it becomes unnecessary to neutralize, with the result that clogging of the lines with gypsum which is formed after the neutralization does not take place.
. (viii) Ingen problemer med kalkforurensning. Mens problemer gjÞr seg gjeldende med kalk i pulverform p.g.a. stÞvforu-rensning og i noen tilfelle - avhengig av kalkens opprinnelse - p.g.a. krominnholdet, er det ved fremgangsmÄten i fÞlge oppfinnelsen ikke nÞdvendig Ä ta disse problemer i' betraktning. ' . (viii) No lime contamination problems. While problems arise with lime in powder form due to dust pollution and in some cases - depending on the origin of the lime - due to the chromium content, it is not necessary to take these problems into account in the method according to the invention. '
(ix) Den letthet med hvilken utstyret kan tillempes arbeiderfri operasjon. Ved den tidligere kjente metode er det nÞdvendig Ä tilfÞre kalk i pulverform til utstyret hvor den opplÞses i vann. Dette er unÞdvendig ved fremgangsmÄten i fÞlge oppfinnelsen, hvor arbeiderfri operasjon lett kan anvendes. (ix) The ease with which the equipment can be adapted to unmanned operation. In the previously known method, it is necessary to add lime in powder form to the equipment where it dissolves in water. This is unnecessary in the method according to the invention, where worker-free operation can easily be used.
(x) Lavere kostnader.(x) Lower costs.
De fÞlgende eksempler vil ytterligere belyse og illu-strere oppfinnelsen. Mengdeangivelsene er hér som for Þvrig i det foreliggende pÄ vektbasis med mindre annet er sagt. The following examples will further illuminate and illustrate the invention. The quantity specifications are here, as elsewhere in the present, on a weight basis, unless otherwise stated.
FremgangsmÄte:Approach:
PrÞver av slam ble blandet med en pÄ forhÄnd bestemt mengde av hydrogenperoksyd og et metall-ion og deretter, ved en pH innstilt pÄ 9 eller lavere, filtrert og avvannet i labora-torieutstyr som beskrevet nedenfor: Samples of sludge were mixed with a predetermined amount of hydrogen peroxide and a metal ion and then, at a pH set at 9 or lower, filtered and dewatered in laboratory equipment as described below:
(1) Lavtrykks-filtreringsutstyr.(1) Low-pressure filtration equipment.
5 liter av et reagensbehandlet slam ble plassert i en lukket lagerbeholder til hvilken nitrogengass ble innfÞrt under forhÄndsbestemte betingelser med hensyn til trykk og tid for filtreringen. Slammet ble fÞrt under trykk til en pÄ forhÄnd anordnet lukket filtreringsbeholder, i hvilken innholdet av fast stoff ble tilbake pÄ filterduken, og filtratet ble uttatt. Til-fÞrselen av nitrogengass under trykk til lagerbeholderén ble sÄ stoppet, og nitrogengass ble tilfÞrt under trykk direkte til filtreringsbeholderen. Innholdet av fast stoff pÄ filterduken ble avvannet under det anvendte trykk og. tid for komprimering. 5 liters of a reagent-treated sludge was placed in a closed storage container to which nitrogen gas was introduced under predetermined conditions of pressure and time for the filtration. The sludge was passed under pressure to a pre-arranged closed filtration container, in which the solid content was returned to the filter cloth, and the filtrate was withdrawn. The supply of nitrogen gas under pressure to the storage container was then stopped, and nitrogen gas was supplied under pressure directly to the filtration container. The solids content on the filter cloth was dewatered under the applied pressure and. time for compression.
Den sÄledes dannede filterkake ble undersÞkt med hensyn til vekt, tykkelse, avskrelling fra filterduken og vanninnhold. (2) HÞytrykks-filtreringsutstyr (Ukraina-Filter fremstilt av Tsukishima Kikai). 3 m 3 av et reagensbehandlet slam ble tilfÞrt filteret under pumpetrykk i en pÄ forhÄnd bestemt tidsperiode. Deretter ble luft tilfÞrt fra en kompressor under forhÄndsbestemte kompre-sjonsbetingelser for avvanning. Den sÄledes dannede filterkake ble mÄlt pÄ samme mÄte som under (1) ovenfor. The filter cake thus formed was examined with regard to weight, thickness, peeling from the filter cloth and water content. (2) High pressure filtration equipment (Ukraine-Filter manufactured by Tsukishima Kikai). 3 m 3 of a reagent-treated sludge was fed to the filter under pump pressure for a predetermined time period. Air was then supplied from a compressor under predetermined compression conditions for dewatering. The filter cake thus formed was measured in the same way as under (1) above.
Sammenligningseksempel 1Comparative example 1
Til et rÄslam med et faststoffinnhold pÄ 2-3% ble det tilsatt 30-50 vekt-% kalk [ca(0H)2]pÄ basis av f aststof f innholdet og 10-13 vekt-% jern(III)klorid (FeCl3) pÄ basis av faststoffinnholdet. Blandingen ble behandlet i et lite og et stort fil-treringsanlegg. Filtreringen ble utfÞrt under et trykk pÄ' To a raw sludge with a solids content of 2-3%, 30-50% by weight of lime [ca(0H)2] on the basis of the solids content and 10-13% by weight of iron(III) chloride (FeCl3) were added on the basis of the solids content. The mixture was treated in a small and a large filtration plant. The filtration was carried out under a pressure of
3 kg/cm i 6 minutter og komprimeringen ved 10 kg/cm i 10 minutter. Et antall prĂžver ble undersĂžkt, og de erholdte data er angitt i tabell I:(nr. 1-7). 3 kg/cm for 6 minutes and the compression at 10 kg/cm for 10 minutes. A number of samples were examined, and the data obtained are listed in table I: (no. 1-7).
EKSEMPEL 1' EXAMPLE 1'
Til et rÄslam med et faststoffinnhold pÄ 2-5% ble det tilsatt 1-3 vekt-% hydrogenperoksyd ( H^ O^) uttrykt som det rene To a raw sludge with a solids content of 2-5%, 1-3% by weight of hydrogen peroxide (H^O^) was added, expressed as the pure
stoff pÄ basis av faststoffinnholdet og 3-6 vekt-% jern(III)klorid pÄ basis av faststoffinnholdet. Blandingen ble grundig blandet og behandlet i lite og stort filtreringsutstyr. Filtreringen ble utfÞrt under et trykk pÄ o 3 kg/cm 2i.6 minutter og komprimeringen ved 10 kg/cm 2i 10 minutter. Et antall eksempler som represen-terer oppfinnelsen ble utfÞrt, og de erholdte data er angitt i tabell II (nr. 8-17). substance on the basis of the solids content and 3-6% by weight of iron (III) chloride on the basis of the solids content. The mixture was thoroughly mixed and processed in small and large filtration equipment. The filtration was carried out under a pressure of o 3 kg/cm 2 in 6 minutes and the compression at 10 kg/cm 2 in 10 minutes. A number of examples representing the invention were carried out, and the data obtained are shown in table II (no. 8-17).
EKSEMPEL 2 EXAMPLE 2
Det ble foretatt en sammenligning mellom fremgangsmÄten omfattende bruk av kalk og jern(III)klorid og fremgangsmÄten hvor det anvendes hydrogenperoksyd .og jern(III)klorid ved behandling av et avgangsslam inneholdende 0,8% faste stoffer. Filtreringen ble utfÞrt under et trykk pÄ -3 kg/cm 2i 10 minutter og komprimeringen ved 10 kg/cm 2i 15 minutter. Disse data er angitt i tabell III (nr. 18-22) . A comparison was made between the method involving the use of lime and iron (III) chloride and the method where hydrogen peroxide and iron (III) chloride are used when treating a waste sludge containing 0.8% solids. The filtration was carried out under a pressure of -3 kg/cm 2 for 10 minutes and the compression at 10 kg/cm 2 for 15 minutes. These data are shown in table III (no. 18-22).
EKSEMPEL 3 EXAMPLE 3
Det ble foretatt en sammenligning mellom fremgangsmÄten omfattende bruk av kalk og jern(III)klorid og fremgangsmÄten hvor det anvendes hydrogenperoksyd og aluminiumsulf at [a^ (SO^ ) 3~] ved behandling av et oppsluttet slam inneholdende 2% faste stoffer. Disse data er angitt i tabell IV (nr. 23-27) . A comparison was made between the method comprising the use of lime and iron (III) chloride and the method using hydrogen peroxide and aluminum sulphate [a^ (SO^ ) 3~] when treating a cloddy sludge containing 2% solids. These data are shown in table IV (no. 23-27).
Claims (7)
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP50121335A JPS5245582A (en) | 1975-10-09 | 1975-10-09 | Solid-liquid separation method of organic waste fluid sludge |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| NO763422L true NO763422L (en) | 1977-04-13 |
Family
ID=14808701
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| NO763422A NO763422L (en) | 1975-10-09 | 1976-10-07 |
Country Status (11)
| Country | Link |
|---|---|
| JP (1) | JPS5245582A (en) |
| BE (1) | BE847120A (en) |
| CA (1) | CA1074925A (en) |
| DE (1) | DE2645549A1 (en) |
| ES (1) | ES452209A1 (en) |
| FR (1) | FR2327202A1 (en) |
| GB (1) | GB1526129A (en) |
| IT (1) | IT1068543B (en) |
| NL (1) | NL7611142A (en) |
| NO (1) | NO763422L (en) |
| SE (1) | SE7611242L (en) |
Families Citing this family (24)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1597342A (en) * | 1977-03-29 | 1981-09-03 | Courtaulds Ltd | Treatment of aqueous effluents containing a dyestuff |
| JPS5579100A (en) * | 1978-12-08 | 1980-06-14 | Osaka Gas Co Ltd | Treating method for sludge |
| JPS56150481A (en) * | 1980-04-24 | 1981-11-20 | Ebara Infilco Co Ltd | Coagulation process for waste water |
| JPS56173563U (en) * | 1980-05-28 | 1981-12-22 | ||
| JPS574300A (en) * | 1980-06-11 | 1982-01-09 | Ebara Infilco Co Ltd | Dehydration treatment of sludge |
| JPS574299A (en) * | 1980-06-11 | 1982-01-09 | Ebara Infilco Co Ltd | Treatment of sludge |
| JPS5715888A (en) * | 1980-07-02 | 1982-01-27 | Ebara Infilco Co Ltd | Treatment of organic waste water |
| JPS5719086A (en) * | 1980-07-04 | 1982-02-01 | Ebara Infilco Co Ltd | Disposal of organic waste water |
| JPS5724692A (en) * | 1980-07-18 | 1982-02-09 | Ebara Infilco Co Ltd | Disposal of organic waste water |
| JPS5735571U (en) * | 1980-08-07 | 1982-02-24 | ||
| JPS5763197A (en) * | 1980-10-02 | 1982-04-16 | Ebara Infilco Co Ltd | High degree treatment of organic sewage |
| CS228403B1 (en) * | 1982-04-06 | 1984-05-14 | Barta Jiri | Method of concentration biologic,particularly activated sludge |
| ATE27136T1 (en) * | 1983-05-30 | 1987-05-15 | Voest Alpine Ag | PROCESS FOR PRETREATMENT OF SLUDGE TO IMPROVE FLOCKING AND/OR DEWATERING BEHAVIOR IN A FOLLOWING DEWATERING DEVICE. |
| EP0136973A1 (en) * | 1983-08-09 | 1985-04-10 | Benedikt Strausak | Method and composition for disinfecting water |
| JPH069680B2 (en) * | 1986-04-22 | 1994-02-09 | æ„éé±æ„æ ȘćŒäŒç€Ÿ | How to deodorize sludge |
| GB8715155D0 (en) * | 1987-06-25 | 1987-08-05 | Laporte Industries Ltd | Purification of waters |
| US6808481B1 (en) | 1996-10-15 | 2004-10-26 | Erth Technologies, Inc. | Concentric tubular centrifuge |
| US6966874B2 (en) | 1997-10-14 | 2005-11-22 | Erth Technologies, Inc. | Concentric tubular centrifuge |
| AU2002221407A1 (en) | 2001-11-29 | 2003-06-10 | Corporation Biolix | Method for stabilizing and conditioning town and industrial wastewater sludge |
| US7241256B2 (en) | 2003-08-30 | 2007-07-10 | Erth Technologies, Inc. | Centrifuge |
| GB0508622D0 (en) * | 2005-04-28 | 2005-06-08 | Probe Ind Ltd | Method for treating effluent |
| CN102139971A (en) * | 2011-01-26 | 2011-08-03 | äžćœçłæČč性ćŠ(ćäž) | Method and process for advanced treatment of well drilling effluent |
| CN102795752A (en) * | 2011-05-26 | 2012-11-28 | ć±±äžèŽ”ćæŸæçșžäžæéć Źćž | Sludge recycling technology and device thereof in sewage plant |
| CN111762916A (en) * | 2020-07-08 | 2020-10-13 | çæçŻćąéšćäșŹçŻćąç§ćŠç 究æ | Method for treating heavy metal wastewater containing high concentration of suspended solids |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR856954A (en) * | 1938-06-28 | 1940-08-19 | Produits Peroxydes Soc D | Process for the treatment of liquids containing suspended fibrous material |
| FR981086A (en) * | 1948-03-22 | 1951-05-22 | Ici Ltd | Advanced water treatment process |
| US3530067A (en) * | 1968-06-06 | 1970-09-22 | Fmc Corp | Method of treating sewage |
| JPS4915259A (en) * | 1972-06-01 | 1974-02-09 |
-
1975
- 1975-10-09 JP JP50121335A patent/JPS5245582A/en active Pending
-
1976
- 1976-09-22 CA CA261,773A patent/CA1074925A/en not_active Expired
- 1976-10-07 NO NO763422A patent/NO763422L/no unknown
- 1976-10-08 GB GB41960/76A patent/GB1526129A/en not_active Expired
- 1976-10-08 ES ES452209A patent/ES452209A1/en not_active Expired
- 1976-10-08 IT IT28165/76A patent/IT1068543B/en active
- 1976-10-08 NL NL7611142A patent/NL7611142A/en not_active Application Discontinuation
- 1976-10-08 DE DE19762645549 patent/DE2645549A1/en not_active Withdrawn
- 1976-10-08 BE BE171383A patent/BE847120A/en unknown
- 1976-10-08 SE SE7611242A patent/SE7611242L/en unknown
- 1976-10-08 FR FR7630393A patent/FR2327202A1/en not_active Withdrawn
Also Published As
| Publication number | Publication date |
|---|---|
| SE7611242L (en) | 1977-04-10 |
| JPS5245582A (en) | 1977-04-11 |
| ES452209A1 (en) | 1977-11-01 |
| IT1068543B (en) | 1985-03-21 |
| NL7611142A (en) | 1977-04-13 |
| GB1526129A (en) | 1978-09-27 |
| DE2645549A1 (en) | 1977-08-25 |
| CA1074925A (en) | 1980-04-01 |
| FR2327202A1 (en) | 1977-05-06 |
| BE847120A (en) | 1977-04-08 |
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